1. Abstract
       A study was done by the U.S. Geological Survey, in cooperation with the
    State of New Hampshire Department of Environmental Services Water Resources
    Division, to describe the geohydrology and water quality of stratified-
    drift aquifers in the Exeter, Lamprey, and Oyster River Basins in south-
    eastern New Hampshire.  Stratified-drift aquifers discontinously underlie
    56 mi2 (square miles) of the Exeter, Lamprey, and Oyster River basins which
    have a total drainage area of 351 mi2.  Saturated thickness of stratified
    drift within these aquifers locally are as great as 100 feet thick, but
    generally are much less.  Transmissivity values locally are greater than
    3,000 ft2/day but are generally much less.
 
    Descriptors: *Geohydrology, *stratified-drift aquifers, *New Hampshire,
                 *Exeter River Basin, *Lamprey River Basin, *Oyster River
                 Basin, *water-resources data, saturated thickness, trans-
                 missivity
 
 
 2. Applications that use this data
 
   2.1  Intended use of data
       This data can be used to produce maps, illustrations, and perform
    a geographic analysis by federal, state, and local government agencies,
    involved with resource management and plannning. Private engineering
    firms and educational institutions may also benefit from this data.
 
   2.2  Limitations of data
       Transmissivity values should be considered estimates.
 
 3. Attribute discussion
 
      TMAX -- The upper limit of the transmissivity zone
 
      TMIN -- The lower limit of the transmissivity zone
 
      RANGE -- A single value that defines the transmissivity zone
               (in feet squared per day). The folowing table explains
               coding for the RANGE item.
 
              1 = 0
              2 = less than 500
              3 = 0 to 1000
              4 = 500 to 1000
              5 = 0 to 1500
              6 = greater than 1500
              7 = 0 to 2000
              8 = 1000 to 2000
              9 = 2000 to 3000
             10 = greater than 3000
             11 = 2000 to 4000
             12 = greater than 4000
             13 = 4000 to 6000
             14 = greater than 6000
             15 = 4000 to 8000
             16 = greater than 8000
             98 = unable to contour transmissivity
             99 = unable to contour transmissivity
                  and saturated thickness
 
     For example a zone with transmissivty greater than 8000 feet
     squared per day has a TMAX of 99999, a TMIN of 8000, and range
     of 16.
 
 4.  Procedures used to create or automate data
        Transmissivites of stratified-drift aquifers, in feet squared per day
     (ft2/d), were estimated from test-boring logs by calculating hydraulic
     conductivity for specific intervals, multiplying these values by the
     saturated thickness of the interval, and summing the results. Transmis-
     sivity values report by published engineering consultants, were used as
     well as calculating transmissivites from unpublished aquifer test data.
        The transmissivity coverage is a polygon coverage where each polygon
     represents a range a transmissivity; for example, 0 to 1,000 ft2/d. Some
     polygons are hills of till that protrude the stratified-drift and,
     therefore, have a transmissivty of nearly 0ft2/d. Transmissivities were
     interpreted on 1:24,000 scale-stable mylar USGS quadrangle maps and digi-
     tized by Complex Systems Research in Durham, NH into ARC/INFO coverages.
     The quadrangle maps were then merged into one study-wide coverage and
     edited for errors and discrepancies.
        The coverage was further edited in 1997 by the U.S. Geological Survey.
     1:24000 scale hydrography derived from USGS digital line graphs was used
     to erase areas where water bodies occured. Later the attribute items were
     updated and edited to match the data structure of the other study areas for
     the state.
 
 
 5.  Revisions made to data
        Revision 1.0 after colleague and editorial review.
 
 6.  Reviews applied to data
        Data was reviewed by the USGS and N.H. Dept. of Environmental Services,
     Water Resources Division.
 
 7.  Related spatial and tabular data sets and programs
        Other data sets available from this study include, aquifer boundaries,
     saturated thickness, and water table contours.
 
 8.  References cited
     GEOHYDROLOGY AND WATER QUALITY OF STRATIFIED-DRIFT AQUIFERS IN THE
     EXETER, LAMPREY, AND OYSTER RIVER BASINS, SOUTHEASTERN NEW HAMPSHIRE.
     by Richard Bridge Moore
     U.S. Geological Survey  Water-Resources Investigations Report 88-4128
 
 9.  Notes:
     The Projection is as follows:
     PROJECTION STATE
     UNITS FEET
     DATUM NAD83